Effects Guide (incomplete)
Car
When you enter the Nexus for the first time, a NPC will enter the dancing robot world. Follow her into the door and go north until you see a road. Interact with the car to retrieve the effect.
Zombie
Enter the door with the pyramid on it and head east until you find a purple entrance. This should take you to a desert, where you'll find a dead body. Interact with the body for the zombie effect.
TV
In the dancing robot world, there is a large television set. Enter it and wander around the world until you find a unique TV set. Interacting with it will give you the effect.
Golf Club
In the dancing robot world is a large machine. Interact with it and be transported to a lab in a neighborhood. In one of the houses is a set of stairs. Go down the stairs and interact with the golf club.
Paper
Enter the door with the paper airplane on it. Go north until you see vertical paper(with shadow), go west until you see vertical paper's shadow. And go north you see the paper with blue paints. Interacting with it will give you the effect.